Ana Maria Guerra bore Abílio Manuel Guerra Junqueiro to José António Junqueiro Júnior, a supply trader and farmer. Ana died when Abilio was only three years old.
He made secondary studies in Bragança and at sixteen, he enrolled at the University of Coimbra, to study theology. Two years later, he left to study law, that he concluded in 1873. Then he became secretary of the governor of Angra do Heroísmo, Azores, and later of Viana do Castelo. In 1878, he was elected to the House of Representatives.
In 1885, he at Porto published A velhice do Padre Eterno, which generated strong criticism from Portuguese Catholic Church. After the British Ultimatum and the political crisis associated, he was involved in the political debate in 1891, writing
